1. Field of the Invention
The present invention pertains to a laser marking method, specifically to a method for marking a product and simultaneously making a record label of the product by employing a laser beam.
2. Description of the Prior Art
Conventionally, it has been known that a product is marked or stamped in order to identify the product. For instance, in the automobile industry, it is known that specific information, such as product number, vehicle type, or the like can be provided on a component to be incorporated into a work or vehicle body in order to distinguish the component from others to thereby facilitate on assembly process. Japanese Patent Public Disclosure No. 58-67575, laid open to the public on Apr. 22, 1983, discloses a method for providing such information on a component by utilizing a paint containing a ferromagnetic material wherein the ferromagnetic material in the paint is magnetized to be provided with specific vehicle information after coating the paint on the component. Therefore the information can be read after coating. Japanese Patent Public Disclosure No. 59-45091 laid open to the public on Mar. 13. 1984, discloses a device for marking a product or work with a laser beam. Further, it has been known to form a label having information identical with a mark formed on a work after an assembling process. In the case where it is necessary to form both such mark on the work and label, it is desirable to form them simultaneously so as to simplify the marking process and improve the reliability in the identification of the information between the label and the mark. In preparing such a label, there has been known to use a method for producing one or more labels identical with a mark at the saem time when the mark is mechanically formed on a work or vehicle component by employing a marking press. In this method, the labels are disposed on the surface of the work, pressed by the marking press so as to form a mark showing a certain vehicle information and peeled off from the work. However, a problem occurs in the method in that certain portions, such as central portions of the character "0" and "8" surrounded by the marked portion may be dropped out from the label element when the label is peeled off from the work because of no connection of the peripheral portion of the label. As a result, it may be difficult to properly read the information shown on the label. Further, where a plurality of duplicated labels are needed, such label materials are disposed on the surface of the work in an overlapped relationship with each other and the marking press is applied over the label materials so that the pressed mark formed on the work becomes unclear as the overlapped or laminated label materials are increased.